Chapter/Index: Introduction | A |
B |
C |
D |
E |
F |
G |
H |
I |
J |
K |
L |
M |
N |
O |
P |
Q |
R |
S |
T |
U |
V |
W |
X |
Y |
Z |
Appendix
Synchrotron X-ray Diffraction
| Synchrotron X-ray Diffraction technique provides high intensity and high resolution, and thus inproves the quality of structure determination. However, there is only one-dimensional (1D) intensity information in powder X-ray diffraction pattern and it is not a good technique to determine the three-dimensional (3D) unit cell dimensions especially if a few weak peaks from an unknown impurity phase are present.
Table 4413 lists the comparison between conventional X-ray diffraction and synchrotron X-ray Diffraction.
Table 4413. Comparison between conventional and synchrotron X-ray Diffraction.
| |
Conventional X-ray diffraction |
Synchrotron X-ray Diffraction |
| Intensity |
Limited intensity |
High intensity |
| Wavelength |
Limited minimum wavelength, thus more absorption by the sample (maximum sample size is limited) |
Smaller, thus minimize absorption |
| Samples |
Need large samples due to limited intensity |
Can be small samples due to high intensity |
| Data acquisition |
Low speed due to limited intensity |
High speed due to high intensity, thus good for fast in situ processes and unstable compounds |
| Signal-to-noise |
Can be low |
High, thus good for weak features (e.g. impurities, satellite reflections, diffuse scattering) |
| Resolution |
Low |
High, thus good for complex structures with big unit cells, fine peak splitting (phase transitions, decomposition), and peak shapes defined by sample properties (strain, particle size) |
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